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2008 Aero Sedan FWD automatic. I'm getting a weird slight shimmy/vibration at very specific ranges of speed, 15-25 and 70-90. The shimmy is more evident through the entire front end of the car at the 15-25 range but at 70+ the steering wheel shakes. Does not matter what gear I'm in. Doesn't change with engine/trans load - it's completely speed-dependent.

It's not the wheels/tires because it happens with both my winter and summer sets exactly the same way, plus the summer set is brand new and was just balanced with zero issues.

Stock OEM Aero suspension, brand new as of a few months ago (struts, shocks, springs, mounts, bearings, sway bar links). New wheel bearings 6 months ago. Tried swapping CV/half shafts, no change. Tried new OEM half shafts, no change. Undercar inspection shows nothing obvious.

To me, I'm left with control arms, tie rod ends, and engine mounts. I don't think it's mounts though because I turned off my engine while at speed on the highway, no change. Anything else I'm missing that I should inspect? I'm at a loss.
 

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Its not about if u serviced ur fluid or bot, it just happen .
The converter lockup clutch slips instead of fully engage causing a mysterious vibration, not only on saab but any car.
Im not saying that definitely is ur problem, but something to consider ..
 

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Just to talk this out a bit more... you say both winter and summer tires are doing it. Did you have both sets mounted and balanced at the same shop? I would find a shop that uses the Hunter Elite roadforce balancer (https://www.hunter.com/wheel-balancers). I ONLY use this on my cars and the results are spectacular. Light years ahead of typical spin job.
 

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Just to talk this out a bit more... you say both winter and summer tires are doing it. Did you have both sets mounted and balanced at the same shop? I would find a shop that uses the Hunter Elite roadforce balancer (https://www.hunter.com/wheel-balancers). I ONLY use this on my cars and the results are spectacular. Light years ahead of typical spin job.
I would absolutely do that, good bye for good old balance, its road force balance era ..
 

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Jack it up and give the front wheels a shake. If it moves with hands at 3 and 9, it's tie rods. If it moves at 6 and 12, then it's the lower arm joint. Or, at least, those are likely.


I've got this on my car after a tough winter for driving: it shimmies a bit at speeds. It'll also change intensity based on road surface but it never goes away. I'm suspecting tie rods and have just been too busy (lazy) to move from denial to action.
 

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Checking your mounts is easy enough. Open the hood, start car. Have an assistant press brake firmly, then shift it into gear. With any torque on the engine you should see it only move slightly. If it jumps at all when going into gear, at least one mount is bad.
 

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Checking your mounts is easy enough. Open the hood, start car. Have an assistant press brake firmly, then shift it into gear. With any torque on the engine you should see it only move slightly. If it jumps at all when going into gear, at least one mount is bad.
Yep, for sure. Just did this on our 9-4X and replaced a bad front mount. I checked the mounts on the 9-3 about a year ago and all looked good during motor torque, but I should do it again.
 

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My 9-3 has at least 2 bad mounts. I have different symptoms than you describe though. I get a noticeably bad popping type noise when accelerating heavily or accelerating when turning. I've checked CV shafts etc. My mounts are completely disintegrated.
 

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2008 Aero Sedan FWD automatic. I'm getting a weird slight shimmy/vibration at very specific ranges of speed, 15-25 and 70-90. The shimmy is more evident through the entire front end of the car at the 15-25 range but at 70+ the steering wheel shakes. Does not matter what gear I'm in. Doesn't change with engine/trans load - it's completely speed-dependent.

Search for a post by LifeOnABoard, subject: "Vibration during take-off and 70-80 MPH." The post is actually mine, I just forgot the password and don't use Gmail anymore... and I currently can't link.

The video at post #6 is worth a watch.

Basically, to cut to the chase, the right drive axle was causing my low speed wobble. The left drive axle was causing the highway wobble. Replace both before anything else. I also posted a way to replace the rear engine mount without removing the exhaust. Can't find that one. But new mounts help mostly with shifting, not with the speed related wobbles..
 

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Search for a post by LifeOnABoard, subject: "Vibration during take-off and 70-80 MPH." The post is actually mine, I just forgot the password and don't use Gmail anymore... and I currently can't link.

The video at post #6 is worth a watch.

Basically, to cut to the chase, the right drive axle was causing my low speed wobble. The left drive axle was causing the highway wobble. Replace both before anything else. I also posted a way to replace the rear engine mount without removing the exhaust. Can't find that one. But new mounts help mostly with shifting, not with the speed related wobbles..
As noted in my first post, I replaced both axles several months ago and didn't notice a change. I installed new GKN Loebro axles, which are the OEM supplier. Maybe they're no good though, I dunno. Definitely appreciate your input though, thank you.
 

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Nuke it from orbit. Only way to be sure.
 

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As noted in my first post, I replaced both axles several months ago and didn't notice a change. I installed new GKN Loebro axles, which are the OEM supplier. Maybe they're no good though, I dunno. Definitely appreciate your input though, thank you.
I guess I didn’t read that far. Was hoping that my results were repeatable. Did you check the intermediate shaft bearing? I’ve concluded that these cars rely too much on bushings. Mine sounds like a NY taxi cab right now. My struts mounts are going bad I think. Lots of creaks and bad highway vibrations
 
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